[unreadable] The overall goal of our research is to develop novel treatment options for problems involving wrist injury. Major trauma centers report that 29% of all injuries involve the hand or wrist. Chronic pain in the wrist can be debilitating and lead to functional disability and even inability to perform activities of daily living (eating, dressing, and personal hygiene). Diagnosis of carpal injuries can be difficult and physicians are forced to diagnose and treat injuries without fully understanding the anatomical components and how they work. Radiographs, arthroscopy, and surgery aid in the diagnosis but are not always adequate because of limited anatomic views and detail. It is believed that carpal instability is far more common than previously thought and that degenerative disease is the late result of static instability (evident on standard radiographs) and may be the late result of undiagnosed predynamic (no radiographic evidence of injury) or dynamic instability (radiographic evidence only when the wrist is loaded). [unreadable] [unreadable] This study will incorporate previous knowledge gained on normal anatomy and kinematics of the wrist. In these studies, we detailed the anatomy and strength of each of the dorsal ligament components and found a much greater and previously unrecognized importance of these structures in normal wrist kinematics and the role they play in preventing carpal instabilities. Video motion analysis will be used to measure kinematics of the individual carpal bones in cadavers. Carpal angles, axes of rotation, and proximity will provide the comparative measures in wrists without injury (normal) and in wrists in various stages of instability. [unreadable] [unreadable] The role of the specific components of the dorsal ligaments and the modes of failure that result in the different dynamic and static classifications of the clinical injury will be analyzed. Specifically, we hope to delineate the specific anatomic components that contribute to kinematic changes early in the sequence of the instability (pre-dynamic), later in the dynamic instability, and finally in the late or static stage of the injury. Finally, we hope to gain information that will evaluate one novel surgical treatment for DISI and serve as a wind tunnel to eventually predict which reconstruction procedures restore normal function. This knowledge will be used to better understand the contribution of specific ligament anatomy to improve the clinical diagnosis (detect early instability), surgical treatment and postsurgical management of this most common type of carpal instability, which if unconnected, will lead to degenerative arthritis of the wrist. It also offers a possible means to use a biomechanic "wind tunnel" to test the soundness of current and possible future types of surgical repair/reconstructions and an alternative to the "wait and see if this repair works" approach. [unreadable] [unreadable]